Improvement in needles for sewing-machines



PATENTED J LY 14, 18681 a. M. ISBELL. NEEDLE FOR SEWING MACHINES.

W131 e 5 gg UNITED STATES.

PATENT. OFFICE] GEORGE M. ISBELL, ou'roeame'ron, oonnnocriou'r.

IMPROVEMENT flu NEEoLE's FOR SEWING-MACHINES.

Specification forming part of Letters Patent No. 79,983,6ated July 14,1868: antedated July 3,1868.

Figure 1 is anelevation ofsaid needle. Fig.-;

2 is a section through the hook at the line at .m. Fig.3 is a section through the shank at the line 3 3 These figures are shown two or three times the usual size of theneedles.

, Heretofore a hooked needle has been usedin machines for sewing boots and shoes. The body of the needle has generally been cylin-, drical and a hook formed at the end. The perforation made by the needle has generally been so large that the threads drawn in do not fill the hole, and aretherefore more liable to move and chafe and cut 0E than would be the case if the threads were drawn tightly into the hole. Besides this, the boot or shoe is not tight on account of the size of these holes. 7

The object of myinye ntion is to shape the needle so that while the strength required is maintained the hole perforated by it shall be as small as possible. I efl'ect these objects byreducingthe'bo'dy a of the needle as much as consistent with the strength required and flattening the same, as shown sectionally in Fig.

3, so that the hole will not be extended widthwise unnecessarilyms the flattening extend down from the sides of the hook I.

I n-order to maintain the necessary strength in the part c, that connects the body of the needlewith the hook, and at the same time give as much space as possible in the hook for the thread, I form a curvature or swell at the back of the book, as represented in Fig. 1. By lengthening the distance between the edge e of the hook and .the inclined inner surface, a, of the hook the thread can draw into an elliptical sectional shape at the part where it passes around the hook. Thus by my construction 'the-hookis capable of being used with a largerthread than in needles Where there is not as muchspace within the hook. The edge e of the hook is made as a half-circle, from which extend the grooves and taper of the point. (See Fig. 2.) With this .circular shape to the edge of the hook thethread is not liable to be cut or injured as it-is drawn out by the needle.

This needle is especially adapted to use in sewing-machines for boots and shoes. 1 What I claim, and desire to secure by Letters Patent, is-

A sewing-machine needle formed, as specified, with the flattened body, the circular edge to the hook, the lengthened opening'in vthe hook, and the curvature or swell at the back of the hook, as and for the purposes set forth. In witness whereof I have hereunto set my signature this 19th day of'July, A. 111867.

GEO. M. ISIBELL.

Witnese'es CHAS. H. SMITH, Gno. T. BmcKNEY. 

